git.oblomov.eu Git - linux-2.6/blob - drivers/block/pktcdvd.c

   1 /*
   2  * Copyright (C) 2000 Jens Axboe <axboe@suse.de>
   3  * Copyright (C) 2001-2004 Peter Osterlund <petero2@telia.com>
   4  *
   5  * May be copied or modified under the terms of the GNU General Public
   6  * License.  See linux/COPYING for more information.
   7  *
   8  * Packet writing layer for ATAPI and SCSI CD-R, CD-RW, DVD-R, and
   9  * DVD-RW devices (aka an exercise in block layer masturbation)
  10  *
  11  *
  12  * TODO: (circa order of when I will fix it)
  13  * - Only able to write on CD-RW media right now.
  14  * - check host application code on media and set it in write page
  15  * - interface for UDF <-> packet to negotiate a new location when a write
  16  *   fails.
  17  * - handle OPC, especially for -RW media
  18  *
  19  * Theory of operation:
  20  *
  21  * We use a custom make_request_fn function that forwards reads directly to
  22  * the underlying CD device. Write requests are either attached directly to
  23  * a live packet_data object, or simply stored sequentially in a list for
  24  * later processing by the kcdrwd kernel thread. This driver doesn't use
  25  * any elevator functionally as defined by the elevator_s struct, but the
  26  * underlying CD device uses a standard elevator.
  27  *
  28  * This strategy makes it possible to do very late merging of IO requests.
  29  * A new bio sent to pkt_make_request can be merged with a live packet_data
  30  * object even if the object is in the data gathering state.
  31  *
  32  *************************************************************************/
  33
  34 #define VERSION_CODE    "v0.2.0a 2004-07-14 Jens Axboe (axboe@suse.de) and petero2@telia.com"
  35
  36 #include <linux/pktcdvd.h>
  37 #include <linux/config.h>
  38 #include <linux/module.h>
  39 #include <linux/types.h>
  40 #include <linux/kernel.h>
  41 #include <linux/kthread.h>
  42 #include <linux/errno.h>
  43 #include <linux/spinlock.h>
  44 #include <linux/file.h>
  45 #include <linux/proc_fs.h>
  46 #include <linux/seq_file.h>
  47 #include <linux/miscdevice.h>
  48 #include <linux/suspend.h>
  49 #include <scsi/scsi_cmnd.h>
  50 #include <scsi/scsi_ioctl.h>
  51
  52 #include <asm/uaccess.h>
  53
  54 #if PACKET_DEBUG
  55 #define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  56 #else
  57 #define DPRINTK(fmt, args...)
  58 #endif
  59
  60 #if PACKET_DEBUG > 1
  61 #define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  62 #else
  63 #define VPRINTK(fmt, args...)
  64 #endif
  65
  66 #define MAX_SPEED 0xffff
  67
  68 #define ZONE(sector, pd) (((sector) + (pd)->offset) & ~((pd)->settings.size - 1))
  69
  70 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
  71 static struct proc_dir_entry *pkt_proc;
  72 static int pkt_major;
  73 static struct semaphore ctl_mutex;      /* Serialize open/close/setup/teardown */
  74 static mempool_t *psd_pool;
  75
  76
  77 static void pkt_bio_finished(struct pktcdvd_device *pd)
  78 {
  79         BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
  80         if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
  81                 VPRINTK("pktcdvd: queue empty\n");
  82                 atomic_set(&pd->iosched.attention, 1);
  83                 wake_up(&pd->wqueue);
  84         }
  85 }
  86
  87 static void pkt_bio_destructor(struct bio *bio)
  88 {
  89         kfree(bio->bi_io_vec);
  90         kfree(bio);
  91 }
  92
  93 static struct bio *pkt_bio_alloc(int nr_iovecs)
  94 {
  95         struct bio_vec *bvl = NULL;
  96         struct bio *bio;
  97
  98         bio = kmalloc(sizeof(struct bio), GFP_KERNEL);
  99         if (!bio)
 100                 goto no_bio;
 101         bio_init(bio);
 102
 103         bvl = kmalloc(nr_iovecs * sizeof(struct bio_vec), GFP_KERNEL);
 104         if (!bvl)
 105                 goto no_bvl;
 106         memset(bvl, 0, nr_iovecs * sizeof(struct bio_vec));
 107
 108         bio->bi_max_vecs = nr_iovecs;
 109         bio->bi_io_vec = bvl;
 110         bio->bi_destructor = pkt_bio_destructor;
 111
 112         return bio;
 113
 114  no_bvl:
 115         kfree(bio);
 116  no_bio:
 117         return NULL;
 118 }
 119
 120 /*
 121  * Allocate a packet_data struct
 122  */
 123 static struct packet_data *pkt_alloc_packet_data(void)
 124 {
 125         int i;
 126         struct packet_data *pkt;
 127
 128         pkt = kmalloc(sizeof(struct packet_data), GFP_KERNEL);
 129         if (!pkt)
 130                 goto no_pkt;
 131         memset(pkt, 0, sizeof(struct packet_data));
 132
 133         pkt->w_bio = pkt_bio_alloc(PACKET_MAX_SIZE);
 134         if (!pkt->w_bio)
 135                 goto no_bio;
 136
 137         for (i = 0; i < PAGES_PER_PACKET; i++) {
 138                 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 139                 if (!pkt->pages[i])
 140                         goto no_page;
 141         }
 142
 143         spin_lock_init(&pkt->lock);
 144
 145         for (i = 0; i < PACKET_MAX_SIZE; i++) {
 146                 struct bio *bio = pkt_bio_alloc(1);
 147                 if (!bio)
 148                         goto no_rd_bio;
 149                 pkt->r_bios[i] = bio;
 150         }
 151
 152         return pkt;
 153
 154 no_rd_bio:
 155         for (i = 0; i < PACKET_MAX_SIZE; i++) {
 156                 struct bio *bio = pkt->r_bios[i];
 157                 if (bio)
 158                         bio_put(bio);
 159         }
 160
 161 no_page:
 162         for (i = 0; i < PAGES_PER_PACKET; i++)
 163                 if (pkt->pages[i])
 164                         __free_page(pkt->pages[i]);
 165         bio_put(pkt->w_bio);
 166 no_bio:
 167         kfree(pkt);
 168 no_pkt:
 169         return NULL;
 170 }
 171
 172 /*
 173  * Free a packet_data struct
 174  */
 175 static void pkt_free_packet_data(struct packet_data *pkt)
 176 {
 177         int i;
 178
 179         for (i = 0; i < PACKET_MAX_SIZE; i++) {
 180                 struct bio *bio = pkt->r_bios[i];
 181                 if (bio)
 182                         bio_put(bio);
 183         }
 184         for (i = 0; i < PAGES_PER_PACKET; i++)
 185                 __free_page(pkt->pages[i]);
 186         bio_put(pkt->w_bio);
 187         kfree(pkt);
 188 }
 189
 190 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 191 {
 192         struct packet_data *pkt, *next;
 193
 194         BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 195
 196         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 197                 pkt_free_packet_data(pkt);
 198         }
 199 }
 200
 201 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 202 {
 203         struct packet_data *pkt;
 204
 205         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 206         INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
 207         spin_lock_init(&pd->cdrw.active_list_lock);
 208         while (nr_packets > 0) {
 209                 pkt = pkt_alloc_packet_data();
 210                 if (!pkt) {
 211                         pkt_shrink_pktlist(pd);
 212                         return 0;
 213                 }
 214                 pkt->id = nr_packets;
 215                 pkt->pd = pd;
 216                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 217                 nr_packets--;
 218         }
 219         return 1;
 220 }
 221
 222 static void *pkt_rb_alloc(unsigned int __nocast gfp_mask, void *data)
 223 {
 224         return kmalloc(sizeof(struct pkt_rb_node), gfp_mask);
 225 }
 226
 227 static void pkt_rb_free(void *ptr, void *data)
 228 {
 229         kfree(ptr);
 230 }
 231
 232 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 233 {
 234         struct rb_node *n = rb_next(&node->rb_node);
 235         if (!n)
 236                 return NULL;
 237         return rb_entry(n, struct pkt_rb_node, rb_node);
 238 }
 239
 240 static inline void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 241 {
 242         rb_erase(&node->rb_node, &pd->bio_queue);
 243         mempool_free(node, pd->rb_pool);
 244         pd->bio_queue_size--;
 245         BUG_ON(pd->bio_queue_size < 0);
 246 }
 247
 248 /*
 249  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 250  */
 251 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 252 {
 253         struct rb_node *n = pd->bio_queue.rb_node;
 254         struct rb_node *next;
 255         struct pkt_rb_node *tmp;
 256
 257         if (!n) {
 258                 BUG_ON(pd->bio_queue_size > 0);
 259                 return NULL;
 260         }
 261
 262         for (;;) {
 263                 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 264                 if (s <= tmp->bio->bi_sector)
 265                         next = n->rb_left;
 266                 else
 267                         next = n->rb_right;
 268                 if (!next)
 269                         break;
 270                 n = next;
 271         }
 272
 273         if (s > tmp->bio->bi_sector) {
 274                 tmp = pkt_rbtree_next(tmp);
 275                 if (!tmp)
 276                         return NULL;
 277         }
 278         BUG_ON(s > tmp->bio->bi_sector);
 279         return tmp;
 280 }
 281
 282 /*
 283  * Insert a node into the pd->bio_queue rb tree.
 284  */
 285 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 286 {
 287         struct rb_node **p = &pd->bio_queue.rb_node;
 288         struct rb_node *parent = NULL;
 289         sector_t s = node->bio->bi_sector;
 290         struct pkt_rb_node *tmp;
 291
 292         while (*p) {
 293                 parent = *p;
 294                 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 295                 if (s < tmp->bio->bi_sector)
 296                         p = &(*p)->rb_left;
 297                 else
 298                         p = &(*p)->rb_right;
 299         }
 300         rb_link_node(&node->rb_node, parent, p);
 301         rb_insert_color(&node->rb_node, &pd->bio_queue);
 302         pd->bio_queue_size++;
 303 }
 304
 305 /*
 306  * Add a bio to a single linked list defined by its head and tail pointers.
 307  */
 308 static inline void pkt_add_list_last(struct bio *bio, struct bio **list_head, struct bio **list_tail)
 309 {
 310         bio->bi_next = NULL;
 311         if (*list_tail) {
 312                 BUG_ON((*list_head) == NULL);
 313                 (*list_tail)->bi_next = bio;
 314                 (*list_tail) = bio;
 315         } else {
 316                 BUG_ON((*list_head) != NULL);
 317                 (*list_head) = bio;
 318                 (*list_tail) = bio;
 319         }
 320 }
 321
 322 /*
 323  * Remove and return the first bio from a single linked list defined by its
 324  * head and tail pointers.
 325  */
 326 static inline struct bio *pkt_get_list_first(struct bio **list_head, struct bio **list_tail)
 327 {
 328         struct bio *bio;
 329
 330         if (*list_head == NULL)
 331                 return NULL;
 332
 333         bio = *list_head;
 334         *list_head = bio->bi_next;
 335         if (*list_head == NULL)
 336                 *list_tail = NULL;
 337
 338         bio->bi_next = NULL;
 339         return bio;
 340 }
 341
 342 /*
 343  * Send a packet_command to the underlying block device and
 344  * wait for completion.
 345  */
 346 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 347 {
 348         char sense[SCSI_SENSE_BUFFERSIZE];
 349         request_queue_t *q;
 350         struct request *rq;
 351         DECLARE_COMPLETION(wait);
 352         int err = 0;
 353
 354         q = bdev_get_queue(pd->bdev);
 355
 356         rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ? WRITE : READ,
 357                              __GFP_WAIT);
 358         rq->errors = 0;
 359         rq->rq_disk = pd->bdev->bd_disk;
 360         rq->bio = NULL;
 361         rq->buffer = NULL;
 362         rq->timeout = 60*HZ;
 363         rq->data = cgc->buffer;
 364         rq->data_len = cgc->buflen;
 365         rq->sense = sense;
 366         memset(sense, 0, sizeof(sense));
 367         rq->sense_len = 0;
 368         rq->flags |= REQ_BLOCK_PC | REQ_HARDBARRIER;
 369         if (cgc->quiet)
 370                 rq->flags |= REQ_QUIET;
 371         memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 372         if (sizeof(rq->cmd) > CDROM_PACKET_SIZE)
 373                 memset(rq->cmd + CDROM_PACKET_SIZE, 0, sizeof(rq->cmd) - CDROM_PACKET_SIZE);
 374
 375         rq->ref_count++;
 376         rq->flags |= REQ_NOMERGE;
 377         rq->waiting = &wait;
 378         rq->end_io = blk_end_sync_rq;
 379         elv_add_request(q, rq, ELEVATOR_INSERT_BACK, 1);
 380         generic_unplug_device(q);
 381         wait_for_completion(&wait);
 382
 383         if (rq->errors)
 384                 err = -EIO;
 385
 386         blk_put_request(rq);
 387         return err;
 388 }
 389
 390 /*
 391  * A generic sense dump / resolve mechanism should be implemented across
 392  * all ATAPI + SCSI devices.
 393  */
 394 static void pkt_dump_sense(struct packet_command *cgc)
 395 {
 396         static char *info[9] = { "No sense", "Recovered error", "Not ready",
 397                                  "Medium error", "Hardware error", "Illegal request",
 398                                  "Unit attention", "Data protect", "Blank check" };
 399         int i;
 400         struct request_sense *sense = cgc->sense;
 401
 402         printk("pktcdvd:");
 403         for (i = 0; i < CDROM_PACKET_SIZE; i++)
 404                 printk(" %02x", cgc->cmd[i]);
 405         printk(" - ");
 406
 407         if (sense == NULL) {
 408                 printk("no sense\n");
 409                 return;
 410         }
 411
 412         printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
 413
 414         if (sense->sense_key > 8) {
 415                 printk(" (INVALID)\n");
 416                 return;
 417         }
 418
 419         printk(" (%s)\n", info[sense->sense_key]);
 420 }
 421
 422 /*
 423  * flush the drive cache to media
 424  */
 425 static int pkt_flush_cache(struct pktcdvd_device *pd)
 426 {
 427         struct packet_command cgc;
 428
 429         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 430         cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 431         cgc.quiet = 1;
 432
 433         /*
 434          * the IMMED bit -- we default to not setting it, although that
 435          * would allow a much faster close, this is safer
 436          */
 437 #if 0
 438         cgc.cmd[1] = 1 << 1;
 439 #endif
 440         return pkt_generic_packet(pd, &cgc);
 441 }
 442
 443 /*
 444  * speed is given as the normal factor, e.g. 4 for 4x
 445  */
 446 static int pkt_set_speed(struct pktcdvd_device *pd, unsigned write_speed, unsigned read_speed)
 447 {
 448         struct packet_command cgc;
 449         struct request_sense sense;
 450         int ret;
 451
 452         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 453         cgc.sense = &sense;
 454         cgc.cmd[0] = GPCMD_SET_SPEED;
 455         cgc.cmd[2] = (read_speed >> 8) & 0xff;
 456         cgc.cmd[3] = read_speed & 0xff;
 457         cgc.cmd[4] = (write_speed >> 8) & 0xff;
 458         cgc.cmd[5] = write_speed & 0xff;
 459
 460         if ((ret = pkt_generic_packet(pd, &cgc)))
 461                 pkt_dump_sense(&cgc);
 462
 463         return ret;
 464 }
 465
 466 /*
 467  * Queue a bio for processing by the low-level CD device. Must be called
 468  * from process context.
 469  */
 470 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio, int high_prio_read)
 471 {
 472         spin_lock(&pd->iosched.lock);
 473         if (bio_data_dir(bio) == READ) {
 474                 pkt_add_list_last(bio, &pd->iosched.read_queue,
 475                                   &pd->iosched.read_queue_tail);
 476                 if (high_prio_read)
 477                         pd->iosched.high_prio_read = 1;
 478         } else {
 479                 pkt_add_list_last(bio, &pd->iosched.write_queue,
 480                                   &pd->iosched.write_queue_tail);
 481         }
 482         spin_unlock(&pd->iosched.lock);
 483
 484         atomic_set(&pd->iosched.attention, 1);
 485         wake_up(&pd->wqueue);
 486 }
 487
 488 /*
 489  * Process the queued read/write requests. This function handles special
 490  * requirements for CDRW drives:
 491  * - A cache flush command must be inserted before a read request if the
 492  *   previous request was a write.
 493  * - Switching between reading and writing is slow, so don't it more often
 494  *   than necessary.
 495  * - Set the read speed according to current usage pattern. When only reading
 496  *   from the device, it's best to use the highest possible read speed, but
 497  *   when switching often between reading and writing, it's better to have the
 498  *   same read and write speeds.
 499  * - Reads originating from user space should have higher priority than reads
 500  *   originating from pkt_gather_data, because some process is usually waiting
 501  *   on reads of the first kind.
 502  */
 503 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 504 {
 505         request_queue_t *q;
 506
 507         if (atomic_read(&pd->iosched.attention) == 0)
 508                 return;
 509         atomic_set(&pd->iosched.attention, 0);
 510
 511         q = bdev_get_queue(pd->bdev);
 512
 513         for (;;) {
 514                 struct bio *bio;
 515                 int reads_queued, writes_queued, high_prio_read;
 516
 517                 spin_lock(&pd->iosched.lock);
 518                 reads_queued = (pd->iosched.read_queue != NULL);
 519                 writes_queued = (pd->iosched.write_queue != NULL);
 520                 if (!reads_queued)
 521                         pd->iosched.high_prio_read = 0;
 522                 high_prio_read = pd->iosched.high_prio_read;
 523                 spin_unlock(&pd->iosched.lock);
 524
 525                 if (!reads_queued && !writes_queued)
 526                         break;
 527
 528                 if (pd->iosched.writing) {
 529                         if (high_prio_read || (!writes_queued && reads_queued)) {
 530                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 531                                         VPRINTK("pktcdvd: write, waiting\n");
 532                                         break;
 533                                 }
 534                                 pkt_flush_cache(pd);
 535                                 pd->iosched.writing = 0;
 536                         }
 537                 } else {
 538                         if (!reads_queued && writes_queued) {
 539                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 540                                         VPRINTK("pktcdvd: read, waiting\n");
 541                                         break;
 542                                 }
 543                                 pd->iosched.writing = 1;
 544                         }
 545                 }
 546
 547                 spin_lock(&pd->iosched.lock);
 548                 if (pd->iosched.writing) {
 549                         bio = pkt_get_list_first(&pd->iosched.write_queue,
 550                                                  &pd->iosched.write_queue_tail);
 551                 } else {
 552                         bio = pkt_get_list_first(&pd->iosched.read_queue,
 553                                                  &pd->iosched.read_queue_tail);
 554                 }
 555                 spin_unlock(&pd->iosched.lock);
 556
 557                 if (!bio)
 558                         continue;
 559
 560                 if (bio_data_dir(bio) == READ)
 561                         pd->iosched.successive_reads += bio->bi_size >> 10;
 562                 else
 563                         pd->iosched.successive_reads = 0;
 564                 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 565                         if (pd->read_speed == pd->write_speed) {
 566                                 pd->read_speed = MAX_SPEED;
 567                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 568                         }
 569                 } else {
 570                         if (pd->read_speed != pd->write_speed) {
 571                                 pd->read_speed = pd->write_speed;
 572                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 573                         }
 574                 }
 575
 576                 atomic_inc(&pd->cdrw.pending_bios);
 577                 generic_make_request(bio);
 578         }
 579 }
 580
 581 /*
 582  * Special care is needed if the underlying block device has a small
 583  * max_phys_segments value.
 584  */
 585 static int pkt_set_segment_merging(struct pktcdvd_device *pd, request_queue_t *q)
 586 {
 587         if ((pd->settings.size << 9) / CD_FRAMESIZE <= q->max_phys_segments) {
 588                 /*
 589                  * The cdrom device can handle one segment/frame
 590                  */
 591                 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 592                 return 0;
 593         } else if ((pd->settings.size << 9) / PAGE_SIZE <= q->max_phys_segments) {
 594                 /*
 595                  * We can handle this case at the expense of some extra memory
 596                  * copies during write operations
 597                  */
 598                 set_bit(PACKET_MERGE_SEGS, &pd->flags);
 599                 return 0;
 600         } else {
 601                 printk("pktcdvd: cdrom max_phys_segments too small\n");
 602                 return -EIO;
 603         }
 604 }
 605
 606 /*
 607  * Copy CD_FRAMESIZE bytes from src_bio into a destination page
 608  */
 609 static void pkt_copy_bio_data(struct bio *src_bio, int seg, int offs, struct page *dst_page, int dst_offs)
 610 {
 611         unsigned int copy_size = CD_FRAMESIZE;
 612
 613         while (copy_size > 0) {
 614                 struct bio_vec *src_bvl = bio_iovec_idx(src_bio, seg);
 615                 void *vfrom = kmap_atomic(src_bvl->bv_page, KM_USER0) +
 616                         src_bvl->bv_offset + offs;
 617                 void *vto = page_address(dst_page) + dst_offs;
 618                 int len = min_t(int, copy_size, src_bvl->bv_len - offs);
 619
 620                 BUG_ON(len < 0);
 621                 memcpy(vto, vfrom, len);
 622                 kunmap_atomic(vfrom, KM_USER0);
 623
 624                 seg++;
 625                 offs = 0;
 626                 dst_offs += len;
 627                 copy_size -= len;
 628         }
 629 }
 630
 631 /*
 632  * Copy all data for this packet to pkt->pages[], so that
 633  * a) The number of required segments for the write bio is minimized, which
 634  *    is necessary for some scsi controllers.
 635  * b) The data can be used as cache to avoid read requests if we receive a
 636  *    new write request for the same zone.
 637  */
 638 static void pkt_make_local_copy(struct packet_data *pkt, struct page **pages, int *offsets)
 639 {
 640         int f, p, offs;
 641
 642         /* Copy all data to pkt->pages[] */
 643         p = 0;
 644         offs = 0;
 645         for (f = 0; f < pkt->frames; f++) {
 646                 if (pages[f] != pkt->pages[p]) {
 647                         void *vfrom = kmap_atomic(pages[f], KM_USER0) + offsets[f];
 648                         void *vto = page_address(pkt->pages[p]) + offs;
 649                         memcpy(vto, vfrom, CD_FRAMESIZE);
 650                         kunmap_atomic(vfrom, KM_USER0);
 651                         pages[f] = pkt->pages[p];
 652                         offsets[f] = offs;
 653                 } else {
 654                         BUG_ON(offsets[f] != offs);
 655                 }
 656                 offs += CD_FRAMESIZE;
 657                 if (offs >= PAGE_SIZE) {
 658                         BUG_ON(offs > PAGE_SIZE);
 659                         offs = 0;
 660                         p++;
 661                 }
 662         }
 663 }
 664
 665 static int pkt_end_io_read(struct bio *bio, unsigned int bytes_done, int err)
 666 {
 667         struct packet_data *pkt = bio->bi_private;
 668         struct pktcdvd_device *pd = pkt->pd;
 669         BUG_ON(!pd);
 670
 671         if (bio->bi_size)
 672                 return 1;
 673
 674         VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
 675                 (unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
 676
 677         if (err)
 678                 atomic_inc(&pkt->io_errors);
 679         if (atomic_dec_and_test(&pkt->io_wait)) {
 680                 atomic_inc(&pkt->run_sm);
 681                 wake_up(&pd->wqueue);
 682         }
 683         pkt_bio_finished(pd);
 684
 685         return 0;
 686 }
 687
 688 static int pkt_end_io_packet_write(struct bio *bio, unsigned int bytes_done, int err)
 689 {
 690         struct packet_data *pkt = bio->bi_private;
 691         struct pktcdvd_device *pd = pkt->pd;
 692         BUG_ON(!pd);
 693
 694         if (bio->bi_size)
 695                 return 1;
 696
 697         VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
 698
 699         pd->stats.pkt_ended++;
 700
 701         pkt_bio_finished(pd);
 702         atomic_dec(&pkt->io_wait);
 703         atomic_inc(&pkt->run_sm);
 704         wake_up(&pd->wqueue);
 705         return 0;
 706 }
 707
 708 /*
 709  * Schedule reads for the holes in a packet
 710  */
 711 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 712 {
 713         int frames_read = 0;
 714         struct bio *bio;
 715         int f;
 716         char written[PACKET_MAX_SIZE];
 717
 718         BUG_ON(!pkt->orig_bios);
 719
 720         atomic_set(&pkt->io_wait, 0);
 721         atomic_set(&pkt->io_errors, 0);
 722
 723         if (pkt->cache_valid) {
 724                 VPRINTK("pkt_gather_data: zone %llx cached\n",
 725                         (unsigned long long)pkt->sector);
 726                 goto out_account;
 727         }
 728
 729         /*
 730          * Figure out which frames we need to read before we can write.
 731          */
 732         memset(written, 0, sizeof(written));
 733         spin_lock(&pkt->lock);
 734         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
 735                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
 736                 int num_frames = bio->bi_size / CD_FRAMESIZE;
 737                 BUG_ON(first_frame < 0);
 738                 BUG_ON(first_frame + num_frames > pkt->frames);
 739                 for (f = first_frame; f < first_frame + num_frames; f++)
 740                         written[f] = 1;
 741         }
 742         spin_unlock(&pkt->lock);
 743
 744         /*
 745          * Schedule reads for missing parts of the packet.
 746          */
 747         for (f = 0; f < pkt->frames; f++) {
 748                 int p, offset;
 749                 if (written[f])
 750                         continue;
 751                 bio = pkt->r_bios[f];
 752                 bio_init(bio);
 753                 bio->bi_max_vecs = 1;
 754                 bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
 755                 bio->bi_bdev = pd->bdev;
 756                 bio->bi_end_io = pkt_end_io_read;
 757                 bio->bi_private = pkt;
 758
 759                 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
 760                 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
 761                 VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
 762                         f, pkt->pages[p], offset);
 763                 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
 764                         BUG();
 765
 766                 atomic_inc(&pkt->io_wait);
 767                 bio->bi_rw = READ;
 768                 pkt_queue_bio(pd, bio, 0);
 769                 frames_read++;
 770         }
 771
 772 out_account:
 773         VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
 774                 frames_read, (unsigned long long)pkt->sector);
 775         pd->stats.pkt_started++;
 776         pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
 777         pd->stats.secs_w += pd->settings.size;
 778 }
 779
 780 /*
 781  * Find a packet matching zone, or the least recently used packet if
 782  * there is no match.
 783  */
 784 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
 785 {
 786         struct packet_data *pkt;
 787
 788         list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
 789                 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
 790                         list_del_init(&pkt->list);
 791                         if (pkt->sector != zone)
 792                                 pkt->cache_valid = 0;
 793                         break;
 794                 }
 795         }
 796         return pkt;
 797 }
 798
 799 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 800 {
 801         if (pkt->cache_valid) {
 802                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 803         } else {
 804                 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
 805         }
 806 }
 807
 808 /*
 809  * recover a failed write, query for relocation if possible
 810  *
 811  * returns 1 if recovery is possible, or 0 if not
 812  *
 813  */
 814 static int pkt_start_recovery(struct packet_data *pkt)
 815 {
 816         /*
 817          * FIXME. We need help from the file system to implement
 818          * recovery handling.
 819          */
 820         return 0;
 821 #if 0
 822         struct request *rq = pkt->rq;
 823         struct pktcdvd_device *pd = rq->rq_disk->private_data;
 824         struct block_device *pkt_bdev;
 825         struct super_block *sb = NULL;
 826         unsigned long old_block, new_block;
 827         sector_t new_sector;
 828
 829         pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
 830         if (pkt_bdev) {
 831                 sb = get_super(pkt_bdev);
 832                 bdput(pkt_bdev);
 833         }
 834
 835         if (!sb)
 836                 return 0;
 837
 838         if (!sb->s_op || !sb->s_op->relocate_blocks)
 839                 goto out;
 840
 841         old_block = pkt->sector / (CD_FRAMESIZE >> 9);
 842         if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
 843                 goto out;
 844
 845         new_sector = new_block * (CD_FRAMESIZE >> 9);
 846         pkt->sector = new_sector;
 847
 848         pkt->bio->bi_sector = new_sector;
 849         pkt->bio->bi_next = NULL;
 850         pkt->bio->bi_flags = 1 << BIO_UPTODATE;
 851         pkt->bio->bi_idx = 0;
 852
 853         BUG_ON(pkt->bio->bi_rw != (1 << BIO_RW));
 854         BUG_ON(pkt->bio->bi_vcnt != pkt->frames);
 855         BUG_ON(pkt->bio->bi_size != pkt->frames * CD_FRAMESIZE);
 856         BUG_ON(pkt->bio->bi_end_io != pkt_end_io_packet_write);
 857         BUG_ON(pkt->bio->bi_private != pkt);
 858
 859         drop_super(sb);
 860         return 1;
 861
 862 out:
 863         drop_super(sb);
 864         return 0;
 865 #endif
 866 }
 867
 868 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
 869 {
 870 #if PACKET_DEBUG > 1
 871         static const char *state_name[] = {
 872                 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
 873         };
 874         enum packet_data_state old_state = pkt->state;
 875         VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
 876                 state_name[old_state], state_name[state]);
 877 #endif
 878         pkt->state = state;
 879 }
 880
 881 /*
 882  * Scan the work queue to see if we can start a new packet.
 883  * returns non-zero if any work was done.
 884  */
 885 static int pkt_handle_queue(struct pktcdvd_device *pd)
 886 {
 887         struct packet_data *pkt, *p;
 888         struct bio *bio = NULL;
 889         sector_t zone = 0; /* Suppress gcc warning */
 890         struct pkt_rb_node *node, *first_node;
 891         struct rb_node *n;
 892
 893         VPRINTK("handle_queue\n");
 894
 895         atomic_set(&pd->scan_queue, 0);
 896
 897         if (list_empty(&pd->cdrw.pkt_free_list)) {
 898                 VPRINTK("handle_queue: no pkt\n");
 899                 return 0;
 900         }
 901
 902         /*
 903          * Try to find a zone we are not already working on.
 904          */
 905         spin_lock(&pd->lock);
 906         first_node = pkt_rbtree_find(pd, pd->current_sector);
 907         if (!first_node) {
 908                 n = rb_first(&pd->bio_queue);
 909                 if (n)
 910                         first_node = rb_entry(n, struct pkt_rb_node, rb_node);
 911         }
 912         node = first_node;
 913         while (node) {
 914                 bio = node->bio;
 915                 zone = ZONE(bio->bi_sector, pd);
 916                 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
 917                         if (p->sector == zone) {
 918                                 bio = NULL;
 919                                 goto try_next_bio;
 920                         }
 921                 }
 922                 break;
 923 try_next_bio:
 924                 node = pkt_rbtree_next(node);
 925                 if (!node) {
 926                         n = rb_first(&pd->bio_queue);
 927                         if (n)
 928                                 node = rb_entry(n, struct pkt_rb_node, rb_node);
 929                 }
 930                 if (node == first_node)
 931                         node = NULL;
 932         }
 933         spin_unlock(&pd->lock);
 934         if (!bio) {
 935                 VPRINTK("handle_queue: no bio\n");
 936                 return 0;
 937         }
 938
 939         pkt = pkt_get_packet_data(pd, zone);
 940         BUG_ON(!pkt);
 941
 942         pd->current_sector = zone + pd->settings.size;
 943         pkt->sector = zone;
 944         pkt->frames = pd->settings.size >> 2;
 945         BUG_ON(pkt->frames > PACKET_MAX_SIZE);
 946         pkt->write_size = 0;
 947
 948         /*
 949          * Scan work queue for bios in the same zone and link them
 950          * to this packet.
 951          */
 952         spin_lock(&pd->lock);
 953         VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
 954         while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
 955                 bio = node->bio;
 956                 VPRINTK("pkt_handle_queue: found zone=%llx\n",
 957                         (unsigned long long)ZONE(bio->bi_sector, pd));
 958                 if (ZONE(bio->bi_sector, pd) != zone)
 959                         break;
 960                 pkt_rbtree_erase(pd, node);
 961                 spin_lock(&pkt->lock);
 962                 pkt_add_list_last(bio, &pkt->orig_bios, &pkt->orig_bios_tail);
 963                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
 964                 spin_unlock(&pkt->lock);
 965         }
 966         spin_unlock(&pd->lock);
 967
 968         pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
 969         pkt_set_state(pkt, PACKET_WAITING_STATE);
 970         atomic_set(&pkt->run_sm, 1);
 971
 972         spin_lock(&pd->cdrw.active_list_lock);
 973         list_add(&pkt->list, &pd->cdrw.pkt_active_list);
 974         spin_unlock(&pd->cdrw.active_list_lock);
 975
 976         return 1;
 977 }
 978
 979 /*
 980  * Assemble a bio to write one packet and queue the bio for processing
 981  * by the underlying block device.
 982  */
 983 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
 984 {
 985         struct bio *bio;
 986         struct page *pages[PACKET_MAX_SIZE];
 987         int offsets[PACKET_MAX_SIZE];
 988         int f;
 989         int frames_write;
 990
 991         for (f = 0; f < pkt->frames; f++) {
 992                 pages[f] = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
 993                 offsets[f] = (f * CD_FRAMESIZE) % PAGE_SIZE;
 994         }
 995
 996         /*
 997          * Fill-in pages[] and offsets[] with data from orig_bios.
 998          */
 999         frames_write = 0;
1000         spin_lock(&pkt->lock);
1001         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
1002                 int segment = bio->bi_idx;
1003                 int src_offs = 0;
1004                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1005                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1006                 BUG_ON(first_frame < 0);
1007                 BUG_ON(first_frame + num_frames > pkt->frames);
1008                 for (f = first_frame; f < first_frame + num_frames; f++) {
1009                         struct bio_vec *src_bvl = bio_iovec_idx(bio, segment);
1010
1011                         while (src_offs >= src_bvl->bv_len) {
1012                                 src_offs -= src_bvl->bv_len;
1013                                 segment++;
1014                                 BUG_ON(segment >= bio->bi_vcnt);
1015                                 src_bvl = bio_iovec_idx(bio, segment);
1016                         }
1017
1018                         if (src_bvl->bv_len - src_offs >= CD_FRAMESIZE) {
1019                                 pages[f] = src_bvl->bv_page;
1020                                 offsets[f] = src_bvl->bv_offset + src_offs;
1021                         } else {
1022                                 pkt_copy_bio_data(bio, segment, src_offs,
1023                                                   pages[f], offsets[f]);
1024                         }
1025                         src_offs += CD_FRAMESIZE;
1026                         frames_write++;
1027                 }
1028         }
1029         pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1030         spin_unlock(&pkt->lock);
1031
1032         VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1033                 frames_write, (unsigned long long)pkt->sector);
1034         BUG_ON(frames_write != pkt->write_size);
1035
1036         if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1037                 pkt_make_local_copy(pkt, pages, offsets);
1038                 pkt->cache_valid = 1;
1039         } else {
1040                 pkt->cache_valid = 0;
1041         }
1042
1043         /* Start the write request */
1044         bio_init(pkt->w_bio);
1045         pkt->w_bio->bi_max_vecs = PACKET_MAX_SIZE;
1046         pkt->w_bio->bi_sector = pkt->sector;
1047         pkt->w_bio->bi_bdev = pd->bdev;
1048         pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1049         pkt->w_bio->bi_private = pkt;
1050         for (f = 0; f < pkt->frames; f++) {
1051                 if ((f + 1 < pkt->frames) && (pages[f + 1] == pages[f]) &&
1052                     (offsets[f + 1] = offsets[f] + CD_FRAMESIZE)) {
1053                         if (!bio_add_page(pkt->w_bio, pages[f], CD_FRAMESIZE * 2, offsets[f]))
1054                                 BUG();
1055                         f++;
1056                 } else {
1057                         if (!bio_add_page(pkt->w_bio, pages[f], CD_FRAMESIZE, offsets[f]))
1058                                 BUG();
1059                 }
1060         }
1061         VPRINTK("pktcdvd: vcnt=%d\n", pkt->w_bio->bi_vcnt);
1062
1063         atomic_set(&pkt->io_wait, 1);
1064         pkt->w_bio->bi_rw = WRITE;
1065         pkt_queue_bio(pd, pkt->w_bio, 0);
1066 }
1067
1068 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1069 {
1070         struct bio *bio, *next;
1071
1072         if (!uptodate)
1073                 pkt->cache_valid = 0;
1074
1075         /* Finish all bios corresponding to this packet */
1076         bio = pkt->orig_bios;
1077         while (bio) {
1078                 next = bio->bi_next;
1079                 bio->bi_next = NULL;
1080                 bio_endio(bio, bio->bi_size, uptodate ? 0 : -EIO);
1081                 bio = next;
1082         }
1083         pkt->orig_bios = pkt->orig_bios_tail = NULL;
1084 }
1085
1086 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1087 {
1088         int uptodate;
1089
1090         VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1091
1092         for (;;) {
1093                 switch (pkt->state) {
1094                 case PACKET_WAITING_STATE:
1095                         if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1096                                 return;
1097
1098                         pkt->sleep_time = 0;
1099                         pkt_gather_data(pd, pkt);
1100                         pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1101                         break;
1102
1103                 case PACKET_READ_WAIT_STATE:
1104                         if (atomic_read(&pkt->io_wait) > 0)
1105                                 return;
1106
1107                         if (atomic_read(&pkt->io_errors) > 0) {
1108                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1109                         } else {
1110                                 pkt_start_write(pd, pkt);
1111                         }
1112                         break;
1113
1114                 case PACKET_WRITE_WAIT_STATE:
1115                         if (atomic_read(&pkt->io_wait) > 0)
1116                                 return;
1117
1118                         if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1119                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1120                         } else {
1121                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1122                         }
1123                         break;
1124
1125                 case PACKET_RECOVERY_STATE:
1126                         if (pkt_start_recovery(pkt)) {
1127                                 pkt_start_write(pd, pkt);
1128                         } else {
1129                                 VPRINTK("No recovery possible\n");
1130                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1131                         }
1132                         break;
1133
1134                 case PACKET_FINISHED_STATE:
1135                         uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1136                         pkt_finish_packet(pkt, uptodate);
1137                         return;
1138
1139                 default:
1140                         BUG();
1141                         break;
1142                 }
1143         }
1144 }
1145
1146 static void pkt_handle_packets(struct pktcdvd_device *pd)
1147 {
1148         struct packet_data *pkt, *next;
1149
1150         VPRINTK("pkt_handle_packets\n");
1151
1152         /*
1153          * Run state machine for active packets
1154          */
1155         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1156                 if (atomic_read(&pkt->run_sm) > 0) {
1157                         atomic_set(&pkt->run_sm, 0);
1158                         pkt_run_state_machine(pd, pkt);
1159                 }
1160         }
1161
1162         /*
1163          * Move no longer active packets to the free list
1164          */
1165         spin_lock(&pd->cdrw.active_list_lock);
1166         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1167                 if (pkt->state == PACKET_FINISHED_STATE) {
1168                         list_del(&pkt->list);
1169                         pkt_put_packet_data(pd, pkt);
1170                         pkt_set_state(pkt, PACKET_IDLE_STATE);
1171                         atomic_set(&pd->scan_queue, 1);
1172                 }
1173         }
1174         spin_unlock(&pd->cdrw.active_list_lock);
1175 }
1176
1177 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1178 {
1179         struct packet_data *pkt;
1180         int i;
1181
1182         for (i = 0; i <= PACKET_NUM_STATES; i++)
1183                 states[i] = 0;
1184
1185         spin_lock(&pd->cdrw.active_list_lock);
1186         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1187                 states[pkt->state]++;
1188         }
1189         spin_unlock(&pd->cdrw.active_list_lock);
1190 }
1191
1192 /*
1193  * kcdrwd is woken up when writes have been queued for one of our
1194  * registered devices
1195  */
1196 static int kcdrwd(void *foobar)
1197 {
1198         struct pktcdvd_device *pd = foobar;
1199         struct packet_data *pkt;
1200         long min_sleep_time, residue;
1201
1202         set_user_nice(current, -20);
1203
1204         for (;;) {
1205                 DECLARE_WAITQUEUE(wait, current);
1206
1207                 /*
1208                  * Wait until there is something to do
1209                  */
1210                 add_wait_queue(&pd->wqueue, &wait);
1211                 for (;;) {
1212                         set_current_state(TASK_INTERRUPTIBLE);
1213
1214                         /* Check if we need to run pkt_handle_queue */
1215                         if (atomic_read(&pd->scan_queue) > 0)
1216                                 goto work_to_do;
1217
1218                         /* Check if we need to run the state machine for some packet */
1219                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1220                                 if (atomic_read(&pkt->run_sm) > 0)
1221                                         goto work_to_do;
1222                         }
1223
1224                         /* Check if we need to process the iosched queues */
1225                         if (atomic_read(&pd->iosched.attention) != 0)
1226                                 goto work_to_do;
1227
1228                         /* Otherwise, go to sleep */
1229                         if (PACKET_DEBUG > 1) {
1230                                 int states[PACKET_NUM_STATES];
1231                                 pkt_count_states(pd, states);
1232                                 VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1233                                         states[0], states[1], states[2], states[3],
1234                                         states[4], states[5]);
1235                         }
1236
1237                         min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1238                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1239                                 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1240                                         min_sleep_time = pkt->sleep_time;
1241                         }
1242
1243                         generic_unplug_device(bdev_get_queue(pd->bdev));
1244
1245                         VPRINTK("kcdrwd: sleeping\n");
1246                         residue = schedule_timeout(min_sleep_time);
1247                         VPRINTK("kcdrwd: wake up\n");
1248
1249                         /* make swsusp happy with our thread */
1250                         if (current->flags & PF_FREEZE)
1251                                 refrigerator(PF_FREEZE);
1252
1253                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1254                                 if (!pkt->sleep_time)
1255                                         continue;
1256                                 pkt->sleep_time -= min_sleep_time - residue;
1257                                 if (pkt->sleep_time <= 0) {
1258                                         pkt->sleep_time = 0;
1259                                         atomic_inc(&pkt->run_sm);
1260                                 }
1261                         }
1262
1263                         if (signal_pending(current)) {
1264                                 flush_signals(current);
1265                         }
1266                         if (kthread_should_stop())
1267                                 break;
1268                 }
1269 work_to_do:
1270                 set_current_state(TASK_RUNNING);
1271                 remove_wait_queue(&pd->wqueue, &wait);
1272
1273                 if (kthread_should_stop())
1274                         break;
1275
1276                 /*
1277                  * if pkt_handle_queue returns true, we can queue
1278                  * another request.
1279                  */
1280                 while (pkt_handle_queue(pd))
1281                         ;
1282
1283                 /*
1284                  * Handle packet state machine
1285                  */
1286                 pkt_handle_packets(pd);
1287
1288                 /*
1289                  * Handle iosched queues
1290                  */
1291                 pkt_iosched_process_queue(pd);
1292         }
1293
1294         return 0;
1295 }
1296
1297 static void pkt_print_settings(struct pktcdvd_device *pd)
1298 {
1299         printk("pktcdvd: %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1300         printk("%u blocks, ", pd->settings.size >> 2);
1301         printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1302 }
1303
1304 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1305 {
1306         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1307
1308         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1309         cgc->cmd[2] = page_code | (page_control << 6);
1310         cgc->cmd[7] = cgc->buflen >> 8;
1311         cgc->cmd[8] = cgc->buflen & 0xff;
1312         cgc->data_direction = CGC_DATA_READ;
1313         return pkt_generic_packet(pd, cgc);
1314 }
1315
1316 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1317 {
1318         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1319         memset(cgc->buffer, 0, 2);
1320         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1321         cgc->cmd[1] = 0x10;             /* PF */
1322         cgc->cmd[7] = cgc->buflen >> 8;
1323         cgc->cmd[8] = cgc->buflen & 0xff;
1324         cgc->data_direction = CGC_DATA_WRITE;
1325         return pkt_generic_packet(pd, cgc);
1326 }
1327
1328 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1329 {
1330         struct packet_command cgc;
1331         int ret;
1332
1333         /* set up command and get the disc info */
1334         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1335         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1336         cgc.cmd[8] = cgc.buflen = 2;
1337         cgc.quiet = 1;
1338
1339         if ((ret = pkt_generic_packet(pd, &cgc)))
1340                 return ret;
1341
1342         /* not all drives have the same disc_info length, so requeue
1343          * packet with the length the drive tells us it can supply
1344          */
1345         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1346                      sizeof(di->disc_information_length);
1347
1348         if (cgc.buflen > sizeof(disc_information))
1349                 cgc.buflen = sizeof(disc_information);
1350
1351         cgc.cmd[8] = cgc.buflen;
1352         return pkt_generic_packet(pd, &cgc);
1353 }
1354
1355 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1356 {
1357         struct packet_command cgc;
1358         int ret;
1359
1360         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1361         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1362         cgc.cmd[1] = type & 3;
1363         cgc.cmd[4] = (track & 0xff00) >> 8;
1364         cgc.cmd[5] = track & 0xff;
1365         cgc.cmd[8] = 8;
1366         cgc.quiet = 1;
1367
1368         if ((ret = pkt_generic_packet(pd, &cgc)))
1369                 return ret;
1370
1371         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1372                      sizeof(ti->track_information_length);
1373
1374         if (cgc.buflen > sizeof(track_information))
1375                 cgc.buflen = sizeof(track_information);
1376
1377         cgc.cmd[8] = cgc.buflen;
1378         return pkt_generic_packet(pd, &cgc);
1379 }
1380
1381 static int pkt_get_last_written(struct pktcdvd_device *pd, long *last_written)
1382 {
1383         disc_information di;
1384         track_information ti;
1385         __u32 last_track;
1386         int ret = -1;
1387
1388         if ((ret = pkt_get_disc_info(pd, &di)))
1389                 return ret;
1390
1391         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1392         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1393                 return ret;
1394
1395         /* if this track is blank, try the previous. */
1396         if (ti.blank) {
1397                 last_track--;
1398                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1399                         return ret;
1400         }
1401
1402         /* if last recorded field is valid, return it. */
1403         if (ti.lra_v) {
1404                 *last_written = be32_to_cpu(ti.last_rec_address);
1405         } else {
1406                 /* make it up instead */
1407                 *last_written = be32_to_cpu(ti.track_start) +
1408                                 be32_to_cpu(ti.track_size);
1409                 if (ti.free_blocks)
1410                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1411         }
1412         return 0;
1413 }
1414
1415 /*
1416  * write mode select package based on pd->settings
1417  */
1418 static int pkt_set_write_settings(struct pktcdvd_device *pd)
1419 {
1420         struct packet_command cgc;
1421         struct request_sense sense;
1422         write_param_page *wp;
1423         char buffer[128];
1424         int ret, size;
1425
1426         /* doesn't apply to DVD+RW or DVD-RAM */
1427         if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1428                 return 0;
1429
1430         memset(buffer, 0, sizeof(buffer));
1431         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1432         cgc.sense = &sense;
1433         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1434                 pkt_dump_sense(&cgc);
1435                 return ret;
1436         }
1437
1438         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1439         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1440         if (size > sizeof(buffer))
1441                 size = sizeof(buffer);
1442
1443         /*
1444          * now get it all
1445          */
1446         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1447         cgc.sense = &sense;
1448         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1449                 pkt_dump_sense(&cgc);
1450                 return ret;
1451         }
1452
1453         /*
1454          * write page is offset header + block descriptor length
1455          */
1456         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1457
1458         wp->fp = pd->settings.fp;
1459         wp->track_mode = pd->settings.track_mode;
1460         wp->write_type = pd->settings.write_type;
1461         wp->data_block_type = pd->settings.block_mode;
1462
1463         wp->multi_session = 0;
1464
1465 #ifdef PACKET_USE_LS
1466         wp->link_size = 7;
1467         wp->ls_v = 1;
1468 #endif
1469
1470         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1471                 wp->session_format = 0;
1472                 wp->subhdr2 = 0x20;
1473         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1474                 wp->session_format = 0x20;
1475                 wp->subhdr2 = 8;
1476 #if 0
1477                 wp->mcn[0] = 0x80;
1478                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1479 #endif
1480         } else {
1481                 /*
1482                  * paranoia
1483                  */
1484                 printk("pktcdvd: write mode wrong %d\n", wp->data_block_type);
1485                 return 1;
1486         }
1487         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1488
1489         cgc.buflen = cgc.cmd[8] = size;
1490         if ((ret = pkt_mode_select(pd, &cgc))) {
1491                 pkt_dump_sense(&cgc);
1492                 return ret;
1493         }
1494
1495         pkt_print_settings(pd);
1496         return 0;
1497 }
1498
1499 /*
1500  * 0 -- we can write to this track, 1 -- we can't
1501  */
1502 static int pkt_good_track(track_information *ti)
1503 {
1504         /*
1505          * only good for CD-RW at the moment, not DVD-RW
1506          */
1507
1508         /*
1509          * FIXME: only for FP
1510          */
1511         if (ti->fp == 0)
1512                 return 0;
1513
1514         /*
1515          * "good" settings as per Mt Fuji.
1516          */
1517         if (ti->rt == 0 && ti->blank == 0 && ti->packet == 1)
1518                 return 0;
1519
1520         if (ti->rt == 0 && ti->blank == 1 && ti->packet == 1)
1521                 return 0;
1522
1523         if (ti->rt == 1 && ti->blank == 0 && ti->packet == 1)
1524                 return 0;
1525
1526         printk("pktcdvd: bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1527         return 1;
1528 }
1529
1530 /*
1531  * 0 -- we can write to this disc, 1 -- we can't
1532  */
1533 static int pkt_good_disc(struct pktcdvd_device *pd, disc_information *di)
1534 {
1535         switch (pd->mmc3_profile) {
1536                 case 0x0a: /* CD-RW */
1537                 case 0xffff: /* MMC3 not supported */
1538                         break;
1539                 case 0x1a: /* DVD+RW */
1540                 case 0x13: /* DVD-RW */
1541                 case 0x12: /* DVD-RAM */
1542                         return 0;
1543                 default:
1544                         printk("pktcdvd: Wrong disc profile (%x)\n", pd->mmc3_profile);
1545                         return 1;
1546         }
1547
1548         /*
1549          * for disc type 0xff we should probably reserve a new track.
1550          * but i'm not sure, should we leave this to user apps? probably.
1551          */
1552         if (di->disc_type == 0xff) {
1553                 printk("pktcdvd: Unknown disc. No track?\n");
1554                 return 1;
1555         }
1556
1557         if (di->disc_type != 0x20 && di->disc_type != 0) {
1558                 printk("pktcdvd: Wrong disc type (%x)\n", di->disc_type);
1559                 return 1;
1560         }
1561
1562         if (di->erasable == 0) {
1563                 printk("pktcdvd: Disc not erasable\n");
1564                 return 1;
1565         }
1566
1567         if (di->border_status == PACKET_SESSION_RESERVED) {
1568                 printk("pktcdvd: Can't write to last track (reserved)\n");
1569                 return 1;
1570         }
1571
1572         return 0;
1573 }
1574
1575 static int pkt_probe_settings(struct pktcdvd_device *pd)
1576 {
1577         struct packet_command cgc;
1578         unsigned char buf[12];
1579         disc_information di;
1580         track_information ti;
1581         int ret, track;
1582
1583         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1584         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1585         cgc.cmd[8] = 8;
1586         ret = pkt_generic_packet(pd, &cgc);
1587         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1588
1589         memset(&di, 0, sizeof(disc_information));
1590         memset(&ti, 0, sizeof(track_information));
1591
1592         if ((ret = pkt_get_disc_info(pd, &di))) {
1593                 printk("failed get_disc\n");
1594                 return ret;
1595         }
1596
1597         if (pkt_good_disc(pd, &di))
1598                 return -ENXIO;
1599
1600         switch (pd->mmc3_profile) {
1601                 case 0x1a: /* DVD+RW */
1602                         printk("pktcdvd: inserted media is DVD+RW\n");
1603                         break;
1604                 case 0x13: /* DVD-RW */
1605                         printk("pktcdvd: inserted media is DVD-RW\n");
1606                         break;
1607                 case 0x12: /* DVD-RAM */
1608                         printk("pktcdvd: inserted media is DVD-RAM\n");
1609                         break;
1610                 default:
1611                         printk("pktcdvd: inserted media is CD-R%s\n", di.erasable ? "W" : "");
1612                         break;
1613         }
1614         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1615
1616         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1617         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1618                 printk("pktcdvd: failed get_track\n");
1619                 return ret;
1620         }
1621
1622         if (pkt_good_track(&ti)) {
1623                 printk("pktcdvd: can't write to this track\n");
1624                 return -ENXIO;
1625         }
1626
1627         /*
1628          * we keep packet size in 512 byte units, makes it easier to
1629          * deal with request calculations.
1630          */
1631         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1632         if (pd->settings.size == 0) {
1633                 printk("pktcdvd: detected zero packet size!\n");
1634                 pd->settings.size = 128;
1635         }
1636         pd->settings.fp = ti.fp;
1637         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1638
1639         if (ti.nwa_v) {
1640                 pd->nwa = be32_to_cpu(ti.next_writable);
1641                 set_bit(PACKET_NWA_VALID, &pd->flags);
1642         }
1643
1644         /*
1645          * in theory we could use lra on -RW media as well and just zero
1646          * blocks that haven't been written yet, but in practice that
1647          * is just a no-go. we'll use that for -R, naturally.
1648          */
1649         if (ti.lra_v) {
1650                 pd->lra = be32_to_cpu(ti.last_rec_address);
1651                 set_bit(PACKET_LRA_VALID, &pd->flags);
1652         } else {
1653                 pd->lra = 0xffffffff;
1654                 set_bit(PACKET_LRA_VALID, &pd->flags);
1655         }
1656
1657         /*
1658          * fine for now
1659          */
1660         pd->settings.link_loss = 7;
1661         pd->settings.write_type = 0;    /* packet */
1662         pd->settings.track_mode = ti.track_mode;
1663
1664         /*
1665          * mode1 or mode2 disc
1666          */
1667         switch (ti.data_mode) {
1668                 case PACKET_MODE1:
1669                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
1670                         break;
1671                 case PACKET_MODE2:
1672                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
1673                         break;
1674                 default:
1675                         printk("pktcdvd: unknown data mode\n");
1676                         return 1;
1677         }
1678         return 0;
1679 }
1680
1681 /*
1682  * enable/disable write caching on drive
1683  */
1684 static int pkt_write_caching(struct pktcdvd_device *pd, int set)
1685 {
1686         struct packet_command cgc;
1687         struct request_sense sense;
1688         unsigned char buf[64];
1689         int ret;
1690
1691         memset(buf, 0, sizeof(buf));
1692         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1693         cgc.sense = &sense;
1694         cgc.buflen = pd->mode_offset + 12;
1695
1696         /*
1697          * caching mode page might not be there, so quiet this command
1698          */
1699         cgc.quiet = 1;
1700
1701         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
1702                 return ret;
1703
1704         buf[pd->mode_offset + 10] |= (!!set << 2);
1705
1706         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1707         ret = pkt_mode_select(pd, &cgc);
1708         if (ret) {
1709                 printk("pktcdvd: write caching control failed\n");
1710                 pkt_dump_sense(&cgc);
1711         } else if (!ret && set)
1712                 printk("pktcdvd: enabled write caching on %s\n", pd->name);
1713         return ret;
1714 }
1715
1716 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1717 {
1718         struct packet_command cgc;
1719
1720         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1721         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1722         cgc.cmd[4] = lockflag ? 1 : 0;
1723         return pkt_generic_packet(pd, &cgc);
1724 }
1725
1726 /*
1727  * Returns drive maximum write speed
1728  */
1729 static int pkt_get_max_speed(struct pktcdvd_device *pd, unsigned *write_speed)
1730 {
1731         struct packet_command cgc;
1732         struct request_sense sense;
1733         unsigned char buf[256+18];
1734         unsigned char *cap_buf;
1735         int ret, offset;
1736
1737         memset(buf, 0, sizeof(buf));
1738         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1739         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1740         cgc.sense = &sense;
1741
1742         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1743         if (ret) {
1744                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
1745                              sizeof(struct mode_page_header);
1746                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1747                 if (ret) {
1748                         pkt_dump_sense(&cgc);
1749                         return ret;
1750                 }
1751         }
1752
1753         offset = 20;                        /* Obsoleted field, used by older drives */
1754         if (cap_buf[1] >= 28)
1755                 offset = 28;                /* Current write speed selected */
1756         if (cap_buf[1] >= 30) {
1757                 /* If the drive reports at least one "Logical Unit Write
1758                  * Speed Performance Descriptor Block", use the information
1759                  * in the first block. (contains the highest speed)
1760                  */
1761                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
1762                 if (num_spdb > 0)
1763                         offset = 34;
1764         }
1765
1766         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
1767         return 0;
1768 }
1769
1770 /* These tables from cdrecord - I don't have orange book */
1771 /* standard speed CD-RW (1-4x) */
1772 static char clv_to_speed[16] = {
1773         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1774            0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1775 };
1776 /* high speed CD-RW (-10x) */
1777 static char hs_clv_to_speed[16] = {
1778         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1779            0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1780 };
1781 /* ultra high speed CD-RW */
1782 static char us_clv_to_speed[16] = {
1783         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1784            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
1785 };
1786
1787 /*
1788  * reads the maximum media speed from ATIP
1789  */
1790 static int pkt_media_speed(struct pktcdvd_device *pd, unsigned *speed)
1791 {
1792         struct packet_command cgc;
1793         struct request_sense sense;
1794         unsigned char buf[64];
1795         unsigned int size, st, sp;
1796         int ret;
1797
1798         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
1799         cgc.sense = &sense;
1800         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1801         cgc.cmd[1] = 2;
1802         cgc.cmd[2] = 4; /* READ ATIP */
1803         cgc.cmd[8] = 2;
1804         ret = pkt_generic_packet(pd, &cgc);
1805         if (ret) {
1806                 pkt_dump_sense(&cgc);
1807                 return ret;
1808         }
1809         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
1810         if (size > sizeof(buf))
1811                 size = sizeof(buf);
1812
1813         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
1814         cgc.sense = &sense;
1815         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1816         cgc.cmd[1] = 2;
1817         cgc.cmd[2] = 4;
1818         cgc.cmd[8] = size;
1819         ret = pkt_generic_packet(pd, &cgc);
1820         if (ret) {
1821                 pkt_dump_sense(&cgc);
1822                 return ret;
1823         }
1824
1825         if (!buf[6] & 0x40) {
1826                 printk("pktcdvd: Disc type is not CD-RW\n");
1827                 return 1;
1828         }
1829         if (!buf[6] & 0x4) {
1830                 printk("pktcdvd: A1 values on media are not valid, maybe not CDRW?\n");
1831                 return 1;
1832         }
1833
1834         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
1835
1836         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
1837
1838         /* Info from cdrecord */
1839         switch (st) {
1840                 case 0: /* standard speed */
1841                         *speed = clv_to_speed[sp];
1842                         break;
1843                 case 1: /* high speed */
1844                         *speed = hs_clv_to_speed[sp];
1845                         break;
1846                 case 2: /* ultra high speed */
1847                         *speed = us_clv_to_speed[sp];
1848                         break;
1849                 default:
1850                         printk("pktcdvd: Unknown disc sub-type %d\n",st);
1851                         return 1;
1852         }
1853         if (*speed) {
1854                 printk("pktcdvd: Max. media speed: %d\n",*speed);
1855                 return 0;
1856         } else {
1857                 printk("pktcdvd: Unknown speed %d for sub-type %d\n",sp,st);
1858                 return 1;
1859         }
1860 }
1861
1862 static int pkt_perform_opc(struct pktcdvd_device *pd)
1863 {
1864         struct packet_command cgc;
1865         struct request_sense sense;
1866         int ret;
1867
1868         VPRINTK("pktcdvd: Performing OPC\n");
1869
1870         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1871         cgc.sense = &sense;
1872         cgc.timeout = 60*HZ;
1873         cgc.cmd[0] = GPCMD_SEND_OPC;
1874         cgc.cmd[1] = 1;
1875         if ((ret = pkt_generic_packet(pd, &cgc)))
1876                 pkt_dump_sense(&cgc);
1877         return ret;
1878 }
1879
1880 static int pkt_open_write(struct pktcdvd_device *pd)
1881 {
1882         int ret;
1883         unsigned int write_speed, media_write_speed, read_speed;
1884
1885         if ((ret = pkt_probe_settings(pd))) {
1886                 DPRINTK("pktcdvd: %s failed probe\n", pd->name);
1887                 return -EIO;
1888         }
1889
1890         if ((ret = pkt_set_write_settings(pd))) {
1891                 DPRINTK("pktcdvd: %s failed saving write settings\n", pd->name);
1892                 return -EIO;
1893         }
1894
1895         pkt_write_caching(pd, USE_WCACHING);
1896
1897         if ((ret = pkt_get_max_speed(pd, &write_speed)))
1898                 write_speed = 16 * 177;
1899         switch (pd->mmc3_profile) {
1900                 case 0x13: /* DVD-RW */
1901                 case 0x1a: /* DVD+RW */
1902                 case 0x12: /* DVD-RAM */
1903                         DPRINTK("pktcdvd: write speed %ukB/s\n", write_speed);
1904                         break;
1905                 default:
1906                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
1907                                 media_write_speed = 16;
1908                         write_speed = min(write_speed, media_write_speed * 177);
1909                         DPRINTK("pktcdvd: write speed %ux\n", write_speed / 176);
1910                         break;
1911         }
1912         read_speed = write_speed;
1913
1914         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
1915                 DPRINTK("pktcdvd: %s couldn't set write speed\n", pd->name);
1916                 return -EIO;
1917         }
1918         pd->write_speed = write_speed;
1919         pd->read_speed = read_speed;
1920
1921         if ((ret = pkt_perform_opc(pd))) {
1922                 DPRINTK("pktcdvd: %s Optimum Power Calibration failed\n", pd->name);
1923         }
1924
1925         return 0;
1926 }
1927
1928 /*
1929  * called at open time.
1930  */
1931 static int pkt_open_dev(struct pktcdvd_device *pd, int write)
1932 {
1933         int ret;
1934         long lba;
1935         request_queue_t *q;
1936
1937         /*
1938          * We need to re-open the cdrom device without O_NONBLOCK to be able
1939          * to read/write from/to it. It is already opened in O_NONBLOCK mode
1940          * so bdget() can't fail.
1941          */
1942         bdget(pd->bdev->bd_dev);
1943         if ((ret = blkdev_get(pd->bdev, FMODE_READ, O_RDONLY)))
1944                 goto out;
1945
1946         if ((ret = pkt_get_last_written(pd, &lba))) {
1947                 printk("pktcdvd: pkt_get_last_written failed\n");
1948                 goto out_putdev;
1949         }
1950
1951         set_capacity(pd->disk, lba << 2);
1952         set_capacity(pd->bdev->bd_disk, lba << 2);
1953         bd_set_size(pd->bdev, (loff_t)lba << 11);
1954
1955         q = bdev_get_queue(pd->bdev);
1956         if (write) {
1957                 if ((ret = pkt_open_write(pd)))
1958                         goto out_putdev;
1959                 /*
1960                  * Some CDRW drives can not handle writes larger than one packet,
1961                  * even if the size is a multiple of the packet size.
1962                  */
1963                 spin_lock_irq(q->queue_lock);
1964                 blk_queue_max_sectors(q, pd->settings.size);
1965                 spin_unlock_irq(q->queue_lock);
1966                 set_bit(PACKET_WRITABLE, &pd->flags);
1967         } else {
1968                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
1969                 clear_bit(PACKET_WRITABLE, &pd->flags);
1970         }
1971
1972         if ((ret = pkt_set_segment_merging(pd, q)))
1973                 goto out_putdev;
1974
1975         if (write)
1976                 printk("pktcdvd: %lukB available on disc\n", lba << 1);
1977
1978         return 0;
1979
1980 out_putdev:
1981         blkdev_put(pd->bdev);
1982 out:
1983         return ret;
1984 }
1985
1986 /*
1987  * called when the device is closed. makes sure that the device flushes
1988  * the internal cache before we close.
1989  */
1990 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
1991 {
1992         if (flush && pkt_flush_cache(pd))
1993                 DPRINTK("pktcdvd: %s not flushing cache\n", pd->name);
1994
1995         pkt_lock_door(pd, 0);
1996
1997         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
1998         blkdev_put(pd->bdev);
1999 }
2000
2001 static struct pktcdvd_device *pkt_find_dev_from_minor(int dev_minor)
2002 {
2003         if (dev_minor >= MAX_WRITERS)
2004                 return NULL;
2005         return pkt_devs[dev_minor];
2006 }
2007
2008 static int pkt_open(struct inode *inode, struct file *file)
2009 {
2010         struct pktcdvd_device *pd = NULL;
2011         int ret;
2012
2013         VPRINTK("pktcdvd: entering open\n");
2014
2015         down(&ctl_mutex);
2016         pd = pkt_find_dev_from_minor(iminor(inode));
2017         if (!pd) {
2018                 ret = -ENODEV;
2019                 goto out;
2020         }
2021         BUG_ON(pd->refcnt < 0);
2022
2023         pd->refcnt++;
2024         if (pd->refcnt == 1) {
2025                 if (pkt_open_dev(pd, file->f_mode & FMODE_WRITE)) {
2026                         ret = -EIO;
2027                         goto out_dec;
2028                 }
2029                 /*
2030                  * needed here as well, since ext2 (among others) may change
2031                  * the blocksize at mount time
2032                  */
2033                 set_blocksize(inode->i_bdev, CD_FRAMESIZE);
2034         }
2035
2036         up(&ctl_mutex);
2037         return 0;
2038
2039 out_dec:
2040         pd->refcnt--;
2041 out:
2042         VPRINTK("pktcdvd: failed open (%d)\n", ret);
2043         up(&ctl_mutex);
2044         return ret;
2045 }
2046
2047 static int pkt_close(struct inode *inode, struct file *file)
2048 {
2049         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2050         int ret = 0;
2051
2052         down(&ctl_mutex);
2053         pd->refcnt--;
2054         BUG_ON(pd->refcnt < 0);
2055         if (pd->refcnt == 0) {
2056                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2057                 pkt_release_dev(pd, flush);
2058         }
2059         up(&ctl_mutex);
2060         return ret;
2061 }
2062
2063
2064 static void *psd_pool_alloc(unsigned int __nocast gfp_mask, void *data)
2065 {
2066         return kmalloc(sizeof(struct packet_stacked_data), gfp_mask);
2067 }
2068
2069 static void psd_pool_free(void *ptr, void *data)
2070 {
2071         kfree(ptr);
2072 }
2073
2074 static int pkt_end_io_read_cloned(struct bio *bio, unsigned int bytes_done, int err)
2075 {
2076         struct packet_stacked_data *psd = bio->bi_private;
2077         struct pktcdvd_device *pd = psd->pd;
2078
2079         if (bio->bi_size)
2080                 return 1;
2081
2082         bio_put(bio);
2083         bio_endio(psd->bio, psd->bio->bi_size, err);
2084         mempool_free(psd, psd_pool);
2085         pkt_bio_finished(pd);
2086         return 0;
2087 }
2088
2089 static int pkt_make_request(request_queue_t *q, struct bio *bio)
2090 {
2091         struct pktcdvd_device *pd;
2092         char b[BDEVNAME_SIZE];
2093         sector_t zone;
2094         struct packet_data *pkt;
2095         int was_empty, blocked_bio;
2096         struct pkt_rb_node *node;
2097
2098         pd = q->queuedata;
2099         if (!pd) {
2100                 printk("pktcdvd: %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2101                 goto end_io;
2102         }
2103
2104         /*
2105          * Clone READ bios so we can have our own bi_end_io callback.
2106          */
2107         if (bio_data_dir(bio) == READ) {
2108                 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2109                 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2110
2111                 psd->pd = pd;
2112                 psd->bio = bio;
2113                 cloned_bio->bi_bdev = pd->bdev;
2114                 cloned_bio->bi_private = psd;
2115                 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2116                 pd->stats.secs_r += bio->bi_size >> 9;
2117                 pkt_queue_bio(pd, cloned_bio, 1);
2118                 return 0;
2119         }
2120
2121         if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2122                 printk("pktcdvd: WRITE for ro device %s (%llu)\n",
2123                         pd->name, (unsigned long long)bio->bi_sector);
2124                 goto end_io;
2125         }
2126
2127         if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2128                 printk("pktcdvd: wrong bio size\n");
2129                 goto end_io;
2130         }
2131
2132         blk_queue_bounce(q, &bio);
2133
2134         zone = ZONE(bio->bi_sector, pd);
2135         VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2136                 (unsigned long long)bio->bi_sector,
2137                 (unsigned long long)(bio->bi_sector + bio_sectors(bio)));
2138
2139         /* Check if we have to split the bio */
2140         {
2141                 struct bio_pair *bp;
2142                 sector_t last_zone;
2143                 int first_sectors;
2144
2145                 last_zone = ZONE(bio->bi_sector + bio_sectors(bio) - 1, pd);
2146                 if (last_zone != zone) {
2147                         BUG_ON(last_zone != zone + pd->settings.size);
2148                         first_sectors = last_zone - bio->bi_sector;
2149                         bp = bio_split(bio, bio_split_pool, first_sectors);
2150                         BUG_ON(!bp);
2151                         pkt_make_request(q, &bp->bio1);
2152                         pkt_make_request(q, &bp->bio2);
2153                         bio_pair_release(bp);
2154                         return 0;
2155                 }
2156         }
2157
2158         /*
2159          * If we find a matching packet in state WAITING or READ_WAIT, we can
2160          * just append this bio to that packet.
2161          */
2162         spin_lock(&pd->cdrw.active_list_lock);
2163         blocked_bio = 0;
2164         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2165                 if (pkt->sector == zone) {
2166                         spin_lock(&pkt->lock);
2167                         if ((pkt->state == PACKET_WAITING_STATE) ||
2168                             (pkt->state == PACKET_READ_WAIT_STATE)) {
2169                                 pkt_add_list_last(bio, &pkt->orig_bios,
2170                                                   &pkt->orig_bios_tail);
2171                                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2172                                 if ((pkt->write_size >= pkt->frames) &&
2173                                     (pkt->state == PACKET_WAITING_STATE)) {
2174                                         atomic_inc(&pkt->run_sm);
2175                                         wake_up(&pd->wqueue);
2176                                 }
2177                                 spin_unlock(&pkt->lock);
2178                                 spin_unlock(&pd->cdrw.active_list_lock);
2179                                 return 0;
2180                         } else {
2181                                 blocked_bio = 1;
2182                         }
2183                         spin_unlock(&pkt->lock);
2184                 }
2185         }
2186         spin_unlock(&pd->cdrw.active_list_lock);
2187
2188         /*
2189          * No matching packet found. Store the bio in the work queue.
2190          */
2191         node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2192         BUG_ON(!node);
2193         node->bio = bio;
2194         spin_lock(&pd->lock);
2195         BUG_ON(pd->bio_queue_size < 0);
2196         was_empty = (pd->bio_queue_size == 0);
2197         pkt_rbtree_insert(pd, node);
2198         spin_unlock(&pd->lock);
2199
2200         /*
2201          * Wake up the worker thread.
2202          */
2203         atomic_set(&pd->scan_queue, 1);
2204         if (was_empty) {
2205                 /* This wake_up is required for correct operation */
2206                 wake_up(&pd->wqueue);
2207         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2208                 /*
2209                  * This wake up is not required for correct operation,
2210                  * but improves performance in some cases.
2211                  */
2212                 wake_up(&pd->wqueue);
2213         }
2214         return 0;
2215 end_io:
2216         bio_io_error(bio, bio->bi_size);
2217         return 0;
2218 }
2219
2220
2221
2222 static int pkt_merge_bvec(request_queue_t *q, struct bio *bio, struct bio_vec *bvec)
2223 {
2224         struct pktcdvd_device *pd = q->queuedata;
2225         sector_t zone = ZONE(bio->bi_sector, pd);
2226         int used = ((bio->bi_sector - zone) << 9) + bio->bi_size;
2227         int remaining = (pd->settings.size << 9) - used;
2228         int remaining2;
2229
2230         /*
2231          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2232          * boundary, pkt_make_request() will split the bio.
2233          */
2234         remaining2 = PAGE_SIZE - bio->bi_size;
2235         remaining = max(remaining, remaining2);
2236
2237         BUG_ON(remaining < 0);
2238         return remaining;
2239 }
2240
2241 static void pkt_init_queue(struct pktcdvd_device *pd)
2242 {
2243         request_queue_t *q = pd->disk->queue;
2244
2245         blk_queue_make_request(q, pkt_make_request);
2246         blk_queue_hardsect_size(q, CD_FRAMESIZE);
2247         blk_queue_max_sectors(q, PACKET_MAX_SECTORS);
2248         blk_queue_merge_bvec(q, pkt_merge_bvec);
2249         q->queuedata = pd;
2250 }
2251
2252 static int pkt_seq_show(struct seq_file *m, void *p)
2253 {
2254         struct pktcdvd_device *pd = m->private;
2255         char *msg;
2256         char bdev_buf[BDEVNAME_SIZE];
2257         int states[PACKET_NUM_STATES];
2258
2259         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2260                    bdevname(pd->bdev, bdev_buf));
2261
2262         seq_printf(m, "\nSettings:\n");
2263         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2264
2265         if (pd->settings.write_type == 0)
2266                 msg = "Packet";
2267         else
2268                 msg = "Unknown";
2269         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2270
2271         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2272         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2273
2274         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2275
2276         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2277                 msg = "Mode 1";
2278         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2279                 msg = "Mode 2";
2280         else
2281                 msg = "Unknown";
2282         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2283
2284         seq_printf(m, "\nStatistics:\n");
2285         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2286         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2287         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2288         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2289         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2290
2291         seq_printf(m, "\nMisc:\n");
2292         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2293         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2294         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2295         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2296         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2297         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2298
2299         seq_printf(m, "\nQueue state:\n");
2300         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2301         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2302         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2303
2304         pkt_count_states(pd, states);
2305         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2306                    states[0], states[1], states[2], states[3], states[4], states[5]);
2307
2308         return 0;
2309 }
2310
2311 static int pkt_seq_open(struct inode *inode, struct file *file)
2312 {
2313         return single_open(file, pkt_seq_show, PDE(inode)->data);
2314 }
2315
2316 static struct file_operations pkt_proc_fops = {
2317         .open   = pkt_seq_open,
2318         .read   = seq_read,
2319         .llseek = seq_lseek,
2320         .release = single_release
2321 };
2322
2323 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2324 {
2325         int i;
2326         int ret = 0;
2327         char b[BDEVNAME_SIZE];
2328         struct proc_dir_entry *proc;
2329         struct block_device *bdev;
2330
2331         if (pd->pkt_dev == dev) {
2332                 printk("pktcdvd: Recursive setup not allowed\n");
2333                 return -EBUSY;
2334         }
2335         for (i = 0; i < MAX_WRITERS; i++) {
2336                 struct pktcdvd_device *pd2 = pkt_devs[i];
2337                 if (!pd2)
2338                         continue;
2339                 if (pd2->bdev->bd_dev == dev) {
2340                         printk("pktcdvd: %s already setup\n", bdevname(pd2->bdev, b));
2341                         return -EBUSY;
2342                 }
2343                 if (pd2->pkt_dev == dev) {
2344                         printk("pktcdvd: Can't chain pktcdvd devices\n");
2345                         return -EBUSY;
2346                 }
2347         }
2348
2349         bdev = bdget(dev);
2350         if (!bdev)
2351                 return -ENOMEM;
2352         ret = blkdev_get(bdev, FMODE_READ, O_RDONLY | O_NONBLOCK);
2353         if (ret)
2354                 return ret;
2355
2356         /* This is safe, since we have a reference from open(). */
2357         __module_get(THIS_MODULE);
2358
2359         if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2360                 printk("pktcdvd: not enough memory for buffers\n");
2361                 ret = -ENOMEM;
2362                 goto out_mem;
2363         }
2364
2365         pd->bdev = bdev;
2366         set_blocksize(bdev, CD_FRAMESIZE);
2367
2368         pkt_init_queue(pd);
2369
2370         atomic_set(&pd->cdrw.pending_bios, 0);
2371         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2372         if (IS_ERR(pd->cdrw.thread)) {
2373                 printk("pktcdvd: can't start kernel thread\n");
2374                 ret = -ENOMEM;
2375                 goto out_thread;
2376         }
2377
2378         proc = create_proc_entry(pd->name, 0, pkt_proc);
2379         if (proc) {
2380                 proc->data = pd;
2381                 proc->proc_fops = &pkt_proc_fops;
2382         }
2383         DPRINTK("pktcdvd: writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2384         return 0;
2385
2386 out_thread:
2387         pkt_shrink_pktlist(pd);
2388 out_mem:
2389         blkdev_put(bdev);
2390         /* This is safe: open() is still holding a reference. */
2391         module_put(THIS_MODULE);
2392         return ret;
2393 }
2394
2395 static int pkt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2396 {
2397         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2398
2399         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd, imajor(inode), iminor(inode));
2400         BUG_ON(!pd);
2401
2402         switch (cmd) {
2403         /*
2404          * forward selected CDROM ioctls to CD-ROM, for UDF
2405          */
2406         case CDROMMULTISESSION:
2407         case CDROMREADTOCENTRY:
2408         case CDROM_LAST_WRITTEN:
2409         case CDROM_SEND_PACKET:
2410         case SCSI_IOCTL_SEND_COMMAND:
2411                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2412
2413         case CDROMEJECT:
2414                 /*
2415                  * The door gets locked when the device is opened, so we
2416                  * have to unlock it or else the eject command fails.
2417                  */
2418                 pkt_lock_door(pd, 0);
2419                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2420
2421         default:
2422                 printk("pktcdvd: Unknown ioctl for %s (%x)\n", pd->name, cmd);
2423                 return -ENOTTY;
2424         }
2425
2426         return 0;
2427 }
2428
2429 static int pkt_media_changed(struct gendisk *disk)
2430 {
2431         struct pktcdvd_device *pd = disk->private_data;
2432         struct gendisk *attached_disk;
2433
2434         if (!pd)
2435                 return 0;
2436         if (!pd->bdev)
2437                 return 0;
2438         attached_disk = pd->bdev->bd_disk;
2439         if (!attached_disk)
2440                 return 0;
2441         return attached_disk->fops->media_changed(attached_disk);
2442 }
2443
2444 static struct block_device_operations pktcdvd_ops = {
2445         .owner =                THIS_MODULE,
2446         .open =                 pkt_open,
2447         .release =              pkt_close,
2448         .ioctl =                pkt_ioctl,
2449         .media_changed =        pkt_media_changed,
2450 };
2451
2452 /*
2453  * Set up mapping from pktcdvd device to CD-ROM device.
2454  */
2455 static int pkt_setup_dev(struct pkt_ctrl_command *ctrl_cmd)
2456 {
2457         int idx;
2458         int ret = -ENOMEM;
2459         struct pktcdvd_device *pd;
2460         struct gendisk *disk;
2461         dev_t dev = new_decode_dev(ctrl_cmd->dev);
2462
2463         for (idx = 0; idx < MAX_WRITERS; idx++)
2464                 if (!pkt_devs[idx])
2465                         break;
2466         if (idx == MAX_WRITERS) {
2467                 printk("pktcdvd: max %d writers supported\n", MAX_WRITERS);
2468                 return -EBUSY;
2469         }
2470
2471         pd = kmalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2472         if (!pd)
2473                 return ret;
2474         memset(pd, 0, sizeof(struct pktcdvd_device));
2475
2476         pd->rb_pool = mempool_create(PKT_RB_POOL_SIZE, pkt_rb_alloc, pkt_rb_free, NULL);
2477         if (!pd->rb_pool)
2478                 goto out_mem;
2479
2480         disk = alloc_disk(1);
2481         if (!disk)
2482                 goto out_mem;
2483         pd->disk = disk;
2484
2485         spin_lock_init(&pd->lock);
2486         spin_lock_init(&pd->iosched.lock);
2487         sprintf(pd->name, "pktcdvd%d", idx);
2488         init_waitqueue_head(&pd->wqueue);
2489         pd->bio_queue = RB_ROOT;
2490
2491         disk->major = pkt_major;
2492         disk->first_minor = idx;
2493         disk->fops = &pktcdvd_ops;
2494         disk->flags = GENHD_FL_REMOVABLE;
2495         sprintf(disk->disk_name, "pktcdvd%d", idx);
2496         disk->private_data = pd;
2497         disk->queue = blk_alloc_queue(GFP_KERNEL);
2498         if (!disk->queue)
2499                 goto out_mem2;
2500
2501         pd->pkt_dev = MKDEV(disk->major, disk->first_minor);
2502         ret = pkt_new_dev(pd, dev);
2503         if (ret)
2504                 goto out_new_dev;
2505
2506         add_disk(disk);
2507         pkt_devs[idx] = pd;
2508         ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2509         return 0;
2510
2511 out_new_dev:
2512         blk_put_queue(disk->queue);
2513 out_mem2:
2514         put_disk(disk);
2515 out_mem:
2516         if (pd->rb_pool)
2517                 mempool_destroy(pd->rb_pool);
2518         kfree(pd);
2519         return ret;
2520 }
2521
2522 /*
2523  * Tear down mapping from pktcdvd device to CD-ROM device.
2524  */
2525 static int pkt_remove_dev(struct pkt_ctrl_command *ctrl_cmd)
2526 {
2527         struct pktcdvd_device *pd;
2528         int idx;
2529         dev_t pkt_dev = new_decode_dev(ctrl_cmd->pkt_dev);
2530
2531         for (idx = 0; idx < MAX_WRITERS; idx++) {
2532                 pd = pkt_devs[idx];
2533                 if (pd && (pd->pkt_dev == pkt_dev))
2534                         break;
2535         }
2536         if (idx == MAX_WRITERS) {
2537                 DPRINTK("pktcdvd: dev not setup\n");
2538                 return -ENXIO;
2539         }
2540
2541         if (pd->refcnt > 0)
2542                 return -EBUSY;
2543
2544         if (!IS_ERR(pd->cdrw.thread))
2545                 kthread_stop(pd->cdrw.thread);
2546
2547         blkdev_put(pd->bdev);
2548
2549         pkt_shrink_pktlist(pd);
2550
2551         remove_proc_entry(pd->name, pkt_proc);
2552         DPRINTK("pktcdvd: writer %s unmapped\n", pd->name);
2553
2554         del_gendisk(pd->disk);
2555         blk_put_queue(pd->disk->queue);
2556         put_disk(pd->disk);
2557
2558         pkt_devs[idx] = NULL;
2559         mempool_destroy(pd->rb_pool);
2560         kfree(pd);
2561
2562         /* This is safe: open() is still holding a reference. */
2563         module_put(THIS_MODULE);
2564         return 0;
2565 }
2566
2567 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2568 {
2569         struct pktcdvd_device *pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2570         if (pd) {
2571                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2572                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2573         } else {
2574                 ctrl_cmd->dev = 0;
2575                 ctrl_cmd->pkt_dev = 0;
2576         }
2577         ctrl_cmd->num_devices = MAX_WRITERS;
2578 }
2579
2580 static int pkt_ctl_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2581 {
2582         void __user *argp = (void __user *)arg;
2583         struct pkt_ctrl_command ctrl_cmd;
2584         int ret = 0;
2585
2586         if (cmd != PACKET_CTRL_CMD)
2587                 return -ENOTTY;
2588
2589         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2590                 return -EFAULT;
2591
2592         switch (ctrl_cmd.command) {
2593         case PKT_CTRL_CMD_SETUP:
2594                 if (!capable(CAP_SYS_ADMIN))
2595                         return -EPERM;
2596                 down(&ctl_mutex);
2597                 ret = pkt_setup_dev(&ctrl_cmd);
2598                 up(&ctl_mutex);
2599                 break;
2600         case PKT_CTRL_CMD_TEARDOWN:
2601                 if (!capable(CAP_SYS_ADMIN))
2602                         return -EPERM;
2603                 down(&ctl_mutex);
2604                 ret = pkt_remove_dev(&ctrl_cmd);
2605                 up(&ctl_mutex);
2606                 break;
2607         case PKT_CTRL_CMD_STATUS:
2608                 down(&ctl_mutex);
2609                 pkt_get_status(&ctrl_cmd);
2610                 up(&ctl_mutex);
2611                 break;
2612         default:
2613                 return -ENOTTY;
2614         }
2615
2616         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2617                 return -EFAULT;
2618         return ret;
2619 }
2620
2621
2622 static struct file_operations pkt_ctl_fops = {
2623         .ioctl   = pkt_ctl_ioctl,
2624         .owner   = THIS_MODULE,
2625 };
2626
2627 static struct miscdevice pkt_misc = {
2628         .minor          = MISC_DYNAMIC_MINOR,
2629         .name           = "pktcdvd",
2630         .devfs_name     = "pktcdvd/control",
2631         .fops           = &pkt_ctl_fops
2632 };
2633
2634 static int __init pkt_init(void)
2635 {
2636         int ret;
2637
2638         psd_pool = mempool_create(PSD_POOL_SIZE, psd_pool_alloc, psd_pool_free, NULL);
2639         if (!psd_pool)
2640                 return -ENOMEM;
2641
2642         ret = register_blkdev(pkt_major, "pktcdvd");
2643         if (ret < 0) {
2644                 printk("pktcdvd: Unable to register block device\n");
2645                 goto out2;
2646         }
2647         if (!pkt_major)
2648                 pkt_major = ret;
2649
2650         ret = misc_register(&pkt_misc);
2651         if (ret) {
2652                 printk("pktcdvd: Unable to register misc device\n");
2653                 goto out;
2654         }
2655
2656         init_MUTEX(&ctl_mutex);
2657
2658         pkt_proc = proc_mkdir("pktcdvd", proc_root_driver);
2659
2660         DPRINTK("pktcdvd: %s\n", VERSION_CODE);
2661         return 0;
2662
2663 out:
2664         unregister_blkdev(pkt_major, "pktcdvd");
2665 out2:
2666         mempool_destroy(psd_pool);
2667         return ret;
2668 }
2669
2670 static void __exit pkt_exit(void)
2671 {
2672         remove_proc_entry("pktcdvd", proc_root_driver);
2673         misc_deregister(&pkt_misc);
2674         unregister_blkdev(pkt_major, "pktcdvd");
2675         mempool_destroy(psd_pool);
2676 }
2677
2678 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
2679 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
2680 MODULE_LICENSE("GPL");
2681
2682 module_init(pkt_init);
2683 module_exit(pkt_exit);